Viral Video of Murdered Teen Charlie Cosser Resurfaces After London-Bound Train Knife Rampage as Britain Cries Out: 'Knife Crimes Must Stop'

A viral TikTok video of slain teenager Charlie Cosser has reignited national outrage over knife crime, just hours after a mass stabbing on a London-bound train left several passengers critically injured.

The emotional clip, originally shared by Charlie's father Martin Cosser, has now reached 4.7 million views, drawing thousands of comments from users demanding an end to Britain's knife-crime epidemic.

The timing of its resurgence, coinciding with the LNER train rampage from Doncaster to London King's Cross, has amplified public anger and grief, with many saying the UK has reached a breaking point in its battle against youth violence.

Martin Cosser: The Father Behind the Movement

Martin Cosser, the Founder and Chief Executive Officer of the charity "Charlie's Promise", has become one of Britain's most recognisable and formidable anti-knife-crime campaigners. Since losing his 17-year-old son in 2023, he has transformed personal tragedy into a national mission for change.

Through social media and school outreach, Cosser's work has reached millions, with his TikTok videos often serving as emotional calls to action. His most recent clip, showing Charlie laughing with friends, is captioned with the words 'Knife crimes have to stop', a message that has deeply resonated in the wake of this week's train attack.

'Every time another young person is killed, it feels like we're reliving the same nightmare,' one user commented, echoing the sentiment of thousands.

The Fatal Party That Shocked Britain

Charlie Cosser was stabbed to death at a house party in Warnham, West Sussex, on 23 July 2023, after an altercation spiralled into violence. His attacker, Yura Varybrus, then 16, inflicted three fatal wounds before fleeing. Charlie died two days later in hospital.

Varybrus was convicted of murder and possession of a bladed article in June 2024 and sentenced to life imprisonment with a minimum term of 16 years. The case became one of the most widely discussed youth-murder trials of the decade and led to an outpouring of grief across the UK.

The London-Bound Train Knife Rampage

On 1 November 2025, just as Cosser's video began trending again, nine people were left fighting for their lives after a violent stabbing spree aboard an LNER train bound for London. The service made an emergency stop at Huntingdon Station in Cambridgeshire, where armed officers stormed the carriages and arrested two suspects within minutes.

Counter-terrorism police are assisting with the investigation, though no motive has yet been confirmed. Authorities have said there is no wider threat to the public, but the incident has intensified fears over Britain's growing wave of knife violence.

'Charlie's Promise' and a Nation's Grief

Since founding Charlie's Promise, Martin Cosser has worked tirelessly to bring anti-knife education to schools nationwide. His charity runs workshops, community events and outreach programmes, reaching thousands of young people each month.

He has repeatedly called for knife-crime awareness to be included in the national curriculum from Key Stage 2, saying prevention must start early. 'We can't wait until children are in their teens to talk about violence,' he said in a recent post. 'By then, for some, it's already too late.'

His advocacy and online presence have made him a respected figure among campaigners and families affected by youth violence. The ITV documentary TikTok: Murder Gone Viral chronicled his mission, cementing his role as the public face of a growing movement for reform.

Britain Demands Change

The simultaneous rise of Charlie's TikTok and the London train tragedy has reignited calls for stronger laws, earlier intervention and a cultural shift in how Britain addresses knife crime.

Across social media, hashtags such as #CharliesPromise, #EndKnifeCrime and #JusticeForCharlie have surged once more.

As one viral comment put it: 'Two years on, we're still losing our children. How many more Charlies before something changes?'

For Martin Cosser, the mission remains deeply personal and painfully urgent. His son's smile, frozen forever in that TikTok clip, continues to echo a message that Britain can no longer afford to ignore: 'Knife crimes have to stop.'